The number of consumers who purchase liquid goods, such as detergent, wine, and other consumables, in bulk has continued to increase over the past decade. A typical detergent container might contain approximately 2 L of liquid detergent. A typical wine bottle might contain approximately 750 mL. To reduce the cost to consumers related to packaging, marketers of liquids such as detergents and wine are increasing their offerings of larger sizes of containers for such fluids. As the containers become larger, they tend to become more and more difficult to pour because the person dispensing the liquid must have adequate wrist strength to controllably pour the liquid. To overcome these difficulties, marketers now offer to consumers containers having a tap dispenser that allow the consumers to dispense fluid without having to lift the container. It is now not uncommon to see detergents, wine, cooking oils, and other bulk liquids packaged in containers having a tap dispenser.
When the container and tap dispenser are placed in operable position the tap dispenser is below the container so that the contents of the container can flow out of the tap dispenser. As fluid flows out of the container the container decreases in volume or the container is vented to allow air to replace the volume of fluid discharged from the container.
Collapsible containers can be used in embodiments in which the container is housed in a rigid carton in what is referred to in the art as a bag in a box type execution. Wine is commonly sold in a bag in a box type execution.
Liquid laundry detergent is presently marketed in a rigid container having a tap dispenser, in particular a press tap dispenser. Since the container is rigid, as laundry detergent is dispensed air is vented into the container to replace the volume of laundry detergent dispensed. Air can be vented into a rigid container through a tap dispenser by flow of air in a direction opposite to the direction of in which liquid is dispensed. When the container is vented in this manner, the flow rate of liquid out of the tap is irregular as bubbles of air enter the liquid stream and move up stream into the container. Irregular dispensing is unattractive to the consumer because dispensing the precise amount of liquid becomes difficult.
To overcome the problem that arises when the pathway for liquid discharge and the venting are the same, the container can be provided with a venting chimney. The venting chimney can be provided in the container at a position that is above the surface of the liquid when the container and tap dispenser are in operable position. The venting chimney can be an additional opening having a threaded closure that opened by the consumer after she places the container and tap dispenser in operable position. Such an approach is used in packaging for TIDE liquid detergent in which the detergent is dispensed via a press tap. Alternatively, the venting chimney can be a one-way check valve in the container that allows air into the container but does not allow liquid to exit the container.
Venting chimneys are undesirable for multiple reasons. Firstly, a venting chimney is an extra part of the container which increases the cost of the packaging. Secondly, venting chimneys occasionally leak during shipping and storage of the container. Thirdly, in some embodiments, the consumer has to open the venting chimney to allow the chimney to function. If the consumer forgets to open the venting chimney or does not know how to open the venting chimney, the consumer may be dissatisfied with the experience of dispensing the product. Consumer dissatisfaction may arise due to unsteady dispensing of the liquid, collapse of the container, cracking of the container, or leakage.
With these limitations of venting chimneys in mind, there is a continuing unaddressed need for technical approaches for venting containers from which the liquid contents are dispensed via tap dispenser.